Eels winger Bevan French scored three tries against the Sharks in Round 17.

Slightly-built Eels speedster Bevan French says he is working hard to get his defence up to NRL standard but won't compromise his trademark pace by trying to bulk up too quickly.

The 20-year-old from Tingha has been a revelation in an injury-ravaged Eels backline of late, racking up nine tries in just six first grade appearances.

However the 85-kilogram rookie has also been a target in defence – not helped by a constantly rotating cast of centre partners – with plenty of tries coming down the Eels right edge in the same period.

A three-try burst to the Panthers down the Eels right side shortly after half-time was costly in last week's 22-18 loss but came against a makeshift edge line-up with lock Beau Scott doing his best in the undermanned backline while back-rowers Manu Ma'u and Kenny Edwards have also had to fill in.

This week, French – a fullback by trade – said he was enjoying the challenge of learning to both play on the wing and adapting to life in the NRL.

"It's only my sixth game… My body's getting used to it week by week. I've still got a bit to learn, especially on the wing there but I'm loving it," French said.

"Scoring tries is a good thing but I've still got a lot to learn in defence. I'm loving my time out there, I think I'm enjoying that more, learning week by week with my defensive roles."

The 85-kilogram fullback was just 76 kilograms when he rocked up at Parramatta and over the past two years tipped the scales at up around 89 kilograms – but the effect on his speed caused him to drop back down to his current playing weight. He said long-term a frame around 90 kilograms should be enough to get him by in the NRL but he needs to build up to it slowly so as not to compromise his pace.

"I think I want to get up around the 90s. The biggest thing for me personally is my speed so I want to get to 90 but I don't want to put it on too quick because when I first moved down I put a bit on too quick and sort of lost my speed a bit," he said.

"I was only 76 when I first came down here so I've put on a bit. Last year or the year before I was around the 89 mark but I lost a bit of speed there so I think for me it's just putting it on slowly."

As for his defence, he said it's an ongoing conversation with his coach Brad Arthur but he isn't using the revolving door of centre partners as any excuse.

"Yeah it is [hard to constantly adjust to new centres] but you can't really use that as an excuse, we've been like that for the past few weeks," he said.

"We've just got to be better with our decision making and like I said I've still got a bit to learn there as well, it's not to do with the forwards switching in there, it's myself as well.

"[Arthur] has spoken to me about it each week. The only way I'm going to learn is to go out there and try and do it in a game so he just keeps telling me to back my decisions. It's a tough decision on the wing, it's only my sixth game there at the moment so I feel like I'm learning each week."